Space
Space, also known as Outer space, is the expanse that exists beyond and between planets. Despite being also known as empty space, the space is not actually empty and works a hard vacuum containing a low density from particles. Along the celestial bodies, the space is studied via astronomy. The space's dark color at Earth might star at least in the terrestrial mesopause onwards. Due to its dual hazards of radiation, this environment is challenging to humans as they must wear suits called space suits. Physical appearance The Space looks a black void, full of stars, planets, natural satellites and asteroids. At the terrestrial night sky, we can see the sky full of stars as dots, in an identical way to how we see the stars in the space, but this is because stars are actually enormous than expected and can be seen from far away due to their brightness. The space's black color might be since there is not light to reflect off in the space between and around the Sun or by a more simple explanation; absence of light, so if the Universe had light, the space might not be black and probably would be white with a glowing of yellow, orange, blue or red. However, the light might probably alter the universe. Discovery In early China at the 2nd century, astronomer Zhang Heng was convinced that the space was indeed infinite. Italian scientist Galileo Galilei knew that air contained mass and was a subject to gravity. In 1640, Galileo presented that an established force resisted a vacuum's formation. The space's modern concept was presumably based off the "Big Bang" cosmology, which was first proposed in 1931 by belgian physicist Georges Lemaître. This theory holds that the universe originated from a form that has since undergone continuous expansion. Another name from this location, named outer space, originated from 1845 by naturalist Alexander von Humboldt. The shorter term, space, is presumably older and originated from 1667 used to refer the region beyond the Earth's sky. Everything mentioned is the reason of space's name and the discovery of the space's existence. Environment The space is challenging to humans to the radiation hazards on it. Humans are required to wear space suits, suits which are commonly used for astronauts to explore the space. According to the television entertainment, a human's head might explode when the space suit is removed, killing the human at the process, but this is because of the hazardous radiation that the space contains. Celestial body types Gallery File:Planet.jpg|Planets, the bodies that usually orbit a star. File:Star.jpg|Stars, the bodies that are made of plasma and compose planetary systems. File:Bluestars.jpg|A closer view of extremely bright stars. Trivia *There are about 100 thousand million stars in the Milky Way. *There are over 30 billion planets in the Milky Way. *The space is one of the largest locations in size, the other being the universe. *It would take a few or several light-years to reach to the stars we can see in the night sky and space. *The space might be at least 28 billion light-years. Category:Astronomy